Description

Analyzes the colors within the current active image and chooses a fixed
number of colors to represent the image.
The goal of the algorithm is to minimize the color difference between the
original image and the output image while minimizing the processing time.
Returns TRUE on success, FALSE, if an error occurred.
colorspace_type must be a ColorspaceType constant, one of the following:
MW_RGBColorspace MW_GRAYColorspace
MW_TransparentColorspace MW_OHTAColorspace
MW_LABColorspace MW_XYZColorspace
MW_YCbCrColorspace MW_YCCColorspace
MW_YIQColorspace MW_YPbPrColorspace
MW_YUVColorspace MW_CMYKColorspace
MW_sRGBColorspace MW_HSBColorspace
MW_HSLColorspace MW_HWBColorspace

Normally, this integer value is zero or one.
A zero or one tells Quantize to choose a optimal tree depth of Log4(number_colors).
A tree of this depth generally allows the best representation of the reference image with the least amount of memory and the fastest computational speed.
In some cases, such as an image with low color dispersion ( a few number of colors ), a value other than Log4(number_colors) is required.
To expand the color tree completely, use a value of 8.

dither

If TRUE, distributes the difference between an original image and the corresponding color reduced algorithm to neighboring pixels along a Hilbert curve.

measure_error

If TRUE, measures the difference between the original and quantized images.
This difference is the total quantization error.
The error is computed by summing over all pixels in an image the distance squared in RGB space between each reference pixel value and its quantized value